Zhang Han, Lam Shiu Hei, Guo Yanzhen, Yang Jianhua, Lu Yao, Shao Lei, Yang Baocheng, Xiao Lehui, Wang Jianfang
Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
Henan Provincial Key Laboratory of Nanocomposites and Applications, Institute of Nanostructured Functional Materials, Huanghe Science and Technology College, Zhengzhou 450006, China.
ACS Appl Mater Interfaces. 2021 Nov 10;13(44):51855-51866. doi: 10.1021/acsami.1c03806. Epub 2021 Apr 28.
Plasmonic hotspots can enhance hot charge carrier generation, offering new opportunities for improving the photocatalytic activity. In this work, eight types of heteronanostructures are synthesized by selectively depositing catalytic metals at the different sites of highly asymmetric Au nanocups for the photocatalytic oxidation of -phenylenediamine. The oxidation of this molecule has so far mainly relied on the use of HO as an oxidizing agent in the presence of an appropriate catalyst. The photocatalytic oxidation under visible light has not been reported before. The Au nanocups with AgPt nanoparticles grown at the opening edge and bottom exhibit the highest photocatalytic activity. The generated hot electrons and holes both participate in the reaction. The hot carriers from the interband and intraband transitions are both utilized. The optimal catalyst shows a favorable activity even under room light. Simulations reveal that the profound electric field enhancement at the hotspots boosts the hot-carrier density in the catalytic nanoparticles, explaining the overwhelming photocatalytic activity of the optimal catalyst.
等离子体热点可以增强热载流子的产生，为提高光催化活性提供了新的机遇。在这项工作中，通过在高度不对称的金纳米杯的不同位置选择性沉积催化金属，合成了八种类型的异质纳米结构，用于对苯二胺的光催化氧化。到目前为止，该分子的氧化主要依赖于在合适催化剂存在下使用过氧化氢作为氧化剂。此前尚未报道过可见光下的光催化氧化。在开口边缘和底部生长有银铂纳米颗粒的金纳米杯表现出最高的光催化活性。产生的热电子和空穴都参与反应。来自带间和带内跃迁的热载流子都得到了利用。即使在室内光线下，最佳催化剂也显示出良好的活性。模拟结果表明，热点处强烈的电场增强提高了催化纳米颗粒中的热载流子密度，这解释了最佳催化剂压倒性的光催化活性。
